Adhesive coated stent and insertion instrument

ABSTRACT

A deployment cartridge is provided to insert a coated stent into a junction formed between two tubular tissue sections. The deployment cartridge includes a pusher and a coated stent contained within the pusher. The pusher includes support structure for engagement with the stent. The stent is coated with a tissue sealant or tissue adhesive. An insertion instrument is also disclosed for advancing the deployment cartridge into the junction formed between the two tubular tissue sections. There is also disclosed a method of facilitating the support and healing at a juncture formed between tubular tissue sections with a coated stent.

BACKGROUND

1. Technical Field

The present disclosure relates to the use of an adhesive coated stent tosupport an anastomotic site. More particularly, the present disclosurerelates to an apparatus and method for inserting an adhesive coatedstent into an anastomotic site formed at a junction between tubulartissue sections.

2. Background of Related Art

During the various surgical procedures it is often necessary to connector join the free ends of two or more tubular tissue sections. Thisprocess is termed forming an anastomosis and the resultant junctionbetween the tubular tissue sections is referred to as an anastomoticsite. Such procedures are common in vascular surgery where it is oftennecessary to join vascular tissue sections during bypass operations,etc. The forming of an anastomosis is also common during colorectalsurgery where a diseased portion of the colon is excised and theresultant sections are rejoined to form an anastomotic site.

The formation of an anastomosis or an anastomotic site is often achievedby folding the free ends of the tissue sections radially inwardly andsecuring them together. The resultant anastomotic junction typicallyresults in a stricture which is a circumscribed narrowing of the joinedhollow tissue structures. For example, in certain colorectal proceduresa circular stapling apparatus is utilized to join the hollow tissuesections. The free ends of the tissue sections are everted radiallyinwardly and staples are passed through the everted edges. Afterstapling, the radially inwardly directed edges of the joined issues forma stricture which temporarily inhibit free flow of fluids or othermaterials through the tubular tissue sections.

Thus, it is desirable to provide a support structure for positioningwithin the anastomotic site to support the anastomotic site andfacilitate healing of the tissue sections.

It is further desirable to provide an adhesive coating on the stent tofacilitate adhesion of the stent to the tissues to promote healing ofthe tissues.

It is still further desirable to provide a stent having a coating oftissue sealant to assist sealing the anastomotic site and preventleakage during healing.

SUMMARY

There is disclosed a deployment cartridge for use in inserting a stentinto an anastomotic site to support the anastomotic site and facilitatethe healing and joining of the tissues at the anastomotic site. Thedeployment cartridge generally includes a hollow pusher and a stentwholly supported within the hollow pusher. The stent is formed as a wiremesh cage having a coating formed on an outer surface. In oneembodiment, the outer coating includes a tissue sealant. In analternative embodiment, the outer coating includes a tissue adhesive. Ina further embodiment, the stent includes an inner coating to facilitatethe passage of materials through the stent.

The pusher includes support structure engageable with the stent tosupport the stent within the pusher. In one embodiment, the supportstructure includes at least one radially inwardly directed projectionengageable with a proximal end of the stent. The pusher is formed with asharp distal tip configured to cut tissue.

There is also disclosed an insertion instrument for use in positioning astent within an anastomotic site. The insertion instrument generallyincludes a handle having an elongate member extending distally from thehandle and a head extending distally from the elongate member. Adeployment cartridge is disposed within the head such that thedeployment cartridge may be extended out of the head. The deploymentcartridge generally includes a pusher and a stent contained within thepusher. The handle includes an actuator operable to advance thedeployment cartridge out of the head.

The insertion instrument additionally includes an anvil memberengageable with the head. The anvil member has an abutment surfaceconfigured to engage the distal end of the stent in order to hold thestent in position within an anastomotic site as the pusher is retractedback into the head. The handle further includes an approximation knobconfigured to approximate the anvil relative to the head.

In one embodiment, the insertion instrument is a surgical staplingapparatus having a head including a plurality of staples and the anvilincludes a plurality of anvil pockets.

There is also disclosed a method of supporting an anastomotic site witha stent. The method generally includes providing an insertion instrumenthaving a deployment cartridge including a pusher and a stent. Theinsertion instrument is positioned within a first tubular tissue sectionand a second tubular tissue section is approximated adjacent the firsttubular tissue section. The deployment cartridge is advanced into thejunction formed between the first and second tubular tissue sections andthe deployment cartridge is advanced into the junction.

An outer surface of the stent is provided with a coating prior toinsertion of the stent within the junction formed between the first andsecond tissue sections. In one embodiment, the outer surface of thestent is coated with a tissue sealant while in an alternative embodimentthe outer surface of the stent is coated with a tissue adhesive.

DESCRIPTION OF THE DRAWINGS

Embodiments of the presently disclosed adhesive coated stent andinsertion instrument are disclosed herein with reference to thedrawings, wherein:

FIG. 1 is a perspective view of an adhesive coated stent;

FIG. 2 is a side view of the adhesive coated stent;

FIG. 3 is an end view of the adhesive coated stent;

FIG. 4 is an enlarged area of detail of FIG. 3 illustrating the adhesivecoating;

FIG. 5 is a side view of the adhesive coated stent undergoing localizedcompressive forces;

FIG. 6 is a perspective view of an insertion instrument for delivery ofthe adhesive coated stent;

FIG. 7 is an enlarged perspective view of the distal end of theinsertion instrument containing the adhesive coated stent;

FIG. 8 is a perspective view of a pusher member of the insertioninstrument containing the adhesive coated stent;

FIG. 9 is perspective view, partially shown in section, of the distalend the insertion instrument positioned in tissue;

FIG. 10 is a perspective view, partially shown in section and phantom,of the insertion instrument inserting the adhesive coated stent into thetissue;

FIG. 11 is a perspective view, partially shown in section, of theadhesive coated stent supporting a stapled anastomotic site; and

FIG. 12 is a perspective view, partially shown in section, of theadhesive coated stent supporting another anastomotic site.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed adhesive coated stent andinsertion instrument will now be described in detail with reference tothe drawings wherein like numerals designate identical or correspondingelements in each of the several views. As is common in the art, the term“proximal” refers to that part or component closer to the user oroperator, i.e. surgeon or physician, while the term “distal” refers tothat part or component further away from the user.

FIGS. 1-3 illustrate an embodiment of the presently disclosed adhesivecoated stent 10. Adhesive coated stent 10 is formed as a generallycylindrical wire mesh cage 12 having a plurality of openings or pores 14extending through wire mesh cage 12. Wire mesh cage 12 is constructed ina manner similar to that typically used to form stents for use invascular angioplasty surgeries. Wire mesh cage 12 may be formed from anyof various suitable materials such as, for example, plastics, ceramics,or metals such as titanium, stainless steel, etc. The dimensions ofpores 14 are chosen based on the intended use of wire mesh cage 12 invarious surgical procedures such as, for example, vascular, colonic,etc.

Wire mesh cage 12 defines a throughbore 16 extending through cage 12from a proximal end 18 to a distal end 20 of cage 12. Throughbore 16provides an avenue for the flow of fluids and other matter through thetissue supported by wire mesh cage 12. It should be noted that, whilewire mesh cage 12 is illustrated as a continuous cylindrical member,wire mesh cage 12 may be formed with a longitudinally split portion suchthat wire mesh cage 12 may be rolled inwardly upon itself to reduce itsouter diameter and facilitate insertion into tissue. Once inserted intothe desired tissue, wire mesh cage 12 would reexpand to its normal outerdiameter after release from an insertion instrument.

Referring now to FIG. 4, adhesive coated stent 10 includes an outercoating 22. Outer coating 22 consists of a tissue adhesive or sealantapplied to an outer surface 24 of wire mesh cage 12. The tissue sealantsmay include various compositions particularly designed to allow tissueto adhere to its self including such materials as fibrin glue's, etc.Coating 22 may be applied to outer surface 24 of wire mesh cage 12 by avarious known procedures, such as, for example, dipping, spraying,static or other deposition methods, etc. by incorporating coating 22into outer surface 24 of wire mesh cage 12, adhesive coated stent 10 isparticularly adapted to seal and/or adhere to the inner surfaces oftubular tissue sections in which adhesive coated stent 10 is disposed.

While not specifically shown, an inner surface 26 of wire mesh cage 12may also be treated or coated with various materials. The materials usedto coat inner surface 26 of wire mesh cage 12 would include variousnonadhesive or relatively slick substances, such as, for example,Teflon, etc. to facilitate the flow of fluids and other materialsthrough throughbore 16 of adhesive coated stent 10.

As best shown in FIG. 5, adhesive coated stent 10 may be formed withvarious areas of relatively differing strengths so as to allow adhesivecoated stent 10 to conform to various areas of the tissue sections beingjoined. Adhesive coated stent 10 generally includes a relativelyweakened central area 28 and relatively stiffened proximal and distalareas 30 and 32 extending from central area 28 towards proximal anddistal ends 18 and 20 of wire mesh cage 12, respectively. As shown, whensubjected to an external circumferential force A, central area 28 maydeflect inwardly to form an inwardly directed circumferential recess 34.Wire mesh cage 12, and, in particular, central area 28, may besufficiently flexible such that circumferential recess 34 slowlydisappears due to the reduction in force A during healing of the joinedtissue sections.

Referring now to FIG. 6, there is disclosed an insertion instrument 36particularly suited for insertion of adhesive coated stent 10 within ananastomotic site formed between two tubular tissue sections. Insertioninstrument 36 generally includes a handle 38 having an elongate tubularmember 40 extending distally from handle 38. A head portion 42 extendsdistally from elongate tubular member 40. Insertion instrument 36additionally includes an anvil member 44 having a cap 46 and a shaft 48extending proximally from cap 46. Cap 46 includes a proximal surface 50.Shaft 48 includes a proximal, tissue penetrating tip 52 for use inpenetrating constricted areas of tubular tissue sections. In order toconnect anvil 44 to head portion 42 of insertion instrument 36, headportion 42 includes a central bore 54 for receipt of shaft 48. Handle 38includes an approximation knob 56 which, when actuated, serves toadvance and retract shaft 48 within bore 54 so as to approximate anvil44 relative to head portion 42 in a manner similar to that used forvarious commonly known surgical stapling or other fastener typeapparatus. One such device, known as a EEA or end to end anastomosisinstrument, is disclosed in U.S. Pat. No. 6,959,851, the entiredisclosure of which is incorporated herein by reference.

Insertion instrument 36 includes a circumferential recess 58 formed inhead portion 42 for receipt of a deployment cartridge 60. As discussedin more detail hereinbelow, deployment cartridge 60 includes adhesivecoated stent 10 as well as a pusher member configured to advanceadhesive coated stent 10 within tubular tissue sections. Handle 38 isprovided with an actuator 62 to advance deployment cartridge 60 out ofcircumferential recess 58 formed in head portion 42. Under surface 50 ofcap 46 includes an abutment surface 64 for engagement with deploymentcartridge 60, and specifically with adhesive coated stent 10, to assistin retaining and separating adhesive coated stent 10 from a pushermember described in a manner hereinbelow.

Insertion instrument 36 can take the form of any of various surgicalinstruments typically used during surgery within tubular tissuesections. As disclosed herein, insertion instrument 36 is in the form ofa surgical stapling apparatus of the type typically used to perform anend to end anastomosis procedure. In this embodiment, insertioninstrument 36 includes an outer ring of staple pockets 66 and an innerring of staple pockets 68 located radially outwardly and inwardly,respectively, of circumferential recess 58. Similarly, an outer ring ofanvil pockets 70 and an inner ring of anvil pockets 72 are formedradially outwardly and inwardly, respectively, of abutment surface 64 inanvil member 44. Thus insertion instrument 36 can eject fasteners, suchas, for example staples, out of staple pockets 66 and 68 and into anvilpockets 70 and 72 to thereby staple together tissue sections capturedthere between.

Referring now to FIGS. 7 and 8, deployment cartridge 60 will now bedescribed. As noted hereinabove, deployment cartridge 60 includesadhesive coated stent 10 and a pusher 74 which is provided to supportadhesive coated stent 10 and advance adhesive coated stent 10 out ofinsertion instrument 36 and into an anastomotic site formed betweentubular tissue sections. Referring now specifically to FIG. 8, pusher 74includes a throughbore 76 extending from a proximal end 78 to a distalend 80 of pusher 74. Adhesive coated stent 10 is entirely disposedwithin throughbore 76 of pusher 74. As shown, pusher 74 includes one ormore support members 82 formed adjacent proximal end 78 and directedradially inwardly within throughbore 76 to engage and support proximalend 18 of adhesive coated stent 10. In one embodiment, pusher 74 is acircular cylindrical knife having a sharp edge or sharp tip 84 formed ondistal end 80 of pusher 74. Sharp tip 84 is provided to cut throughportions of tubular tissue sections after the tubular tissue sectionshave been stapled together.

The use of insertion instrument 36 to insert adhesive coated stent 10within tubular tissue sections will now be described. Referring to FIGS.9-11, and initially with reference to FIG. 9, in an anastomosis typesurgical procedure a disease section of a tubular tissue is excisedleaving a first healthy tubular tissue section B and a second healthytubular tissue section C to be joined. First healthy tubular tissuesection B has a free end D while second healthy tubular tissue section Chas a free end E which are to be joined together to form an anastomosis.

Initially, anvil member 44 is positioned within the first healthytubular tissue section B such that shaft 48 extends out of free end D.Free end D is secured to shaft 48 by sutures or ligatures 86 (which maybe in the form of a “purse string”) connecting free end D to shaft 48.Similarly, head 42 of insertion instrument 36 is positioned withinsecond healthy tubular tissue section C adjacent free end E. In theinitial position, deployment cartridge 60 is wholly contained withinhead portion 42. Once properly positioned, shaft 48 is inserted withinrecess 54 formed in head 42 of insertion instrument 36. Thereafter, freeend E is secured about shaft 48 by sutures or ligatures 88. Thereafter,approximation knob 56 is actuated to draw anvil member 44 togetheragainst head 42 to approximate first and second healthy tissue sectionsB and C.

Referring now to FIG. 10, once approximated, actuator 62 of insertioninstrument 36 is actuated to drive staples 90 out of respective staplepockets 66 and 68, through tissues B and C and into anvil pockets 70 and72 thereby stapling together free ends D an E to form an anastomosisbetween tissue sections B and C. Continued activation of actuator 62drives deployment cartridge 60, including pusher 74 and adhesive coatedstent 10 out of head 42 and across the anastomosis formed between tissuesections B and C. as noted hereinabove, pusher 74 includes a sharpdistal tip 84 which cuts through the excess tissue and allows adhesivecoated stent to be advanced against abutment surface 64 of anvil member44. Abutment surface 64 serves as a surface against which sharp distaltip 84 can engage. Abutment surface 64 additionally forms a surface totemporarily contact and engage distal end 20 (FIG. 5) of adhesive coatedstent 10 such that upon withdrawal of pusher 74 back within head 42 ofinsertion instrument 36, adhesive coated stent 10 remains in placewithin tissue sections B and C.

Referring now to FIG. 11, adhesive coated stent 10 is illustratedpositioned within the anastomosis formed between tissue sections B andC. As noted hereinabove, adhesive coated stent 10 includes a centrallyweakened area 28 which deflects to form inwardly directedcircumferential recess 34 to contain and support free ends D and E,joined by staples 90, as tissue sections B and C heal together. Oncepositioned, adhesive coating 22 adheres to tissue sections B and C tomaintain adhesive coated stent in position. Additionally, where coating22 includes an adhesive or sealant, the adhesive or sealant facilitatesprevention of leakage through the stricture formed at the anastomoticsite and allows time for the tissue sections to heal together properly.

As noted hereinabove, insertion instrument 36 may be used in situationsother than stapling, to position adhesive coated stent across ananastomotic site to facilitate healing of tissues together. As shown,adhesive coated stent 10 is positioned at an anastomotic site F formedbetween tissue sections G and H to facilitate support and healing of theanastomotic site F.

Examples of adhesives which can be employed include protein derived,aldehyde-based adhesive materials, for example, the commerciallyavailable albumin/glutaraldehyde materials sold under the tradedesignation BioGlue™ by Cryolife, Inc., and cyanoacrylate-basedmaterials sold under the trade designations Indermil™ and Derma Bond™ byTyco Healthcare Group, LP and Ethicon Endosurgery, Inc., respectively.Examples of sealants, which can be employed, include fibrin sealants andcollagen-based and synthetic polymer-based tissue sealants. Examples ofcommercially available sealants are synthetic polyethylene glycol-based,hydrogel materials sold under the trade designation CoSeal™ by CohesionTechnologies and Baxter International, Inc. Examples of hemostatmaterials, which can be employed, include fibrin-based, collagen-based,oxidized regenerated cellulose-based and gelatin-based topicalhemostats. Examples of commercially available hemostat materials arefibrinogen-thrombin combination materials sold under the tradedesignations CoStasis™ by Tyco Healthcare Group, LP, and Tisseel™ soldby Baxter International, Inc. Hemostats herein include astringents,e.g., aluminum sulfate, and coagulants.

In certain preferred embodiments, the wound treatment material comprisesa sealant. Such a sealant is desirably a PEG-based material. Examples ofclasses of materials useful as the sealant and/or adhesive includeacrylate or methacrylate functional hydrogels in the presence of abiocompatible photoinitiator, alkyl-cyanoacrylates, isocyanatefunctional macromers with or without amine functional macromers,succinimidyl ester functional macromers with amine or sulfhydrylfunctional macromers, epoxy functional macromers with amine functionalmacromers, mixtures of proteins or polypeptides in the presence ofaldehyde crosslinkers, Genipin, or water-soluble carbodiimides, anionicpolysaccharides in the presence of polyvalent cations, etc.

Some specific materials which may be utilized include isocyanateterminated hydrophilic urethane prepolymers derived from organicpolyisocyanates and oxyethylene-based diols or polyols, including thosedisclosed in U.S. Pat. Nos. 6,702,731 and 6,296,607 and U.S. PublishedPatent Application No. 2004/0068078; alpha-cyanoacrylate based adhesivesincluding those disclosed in U.S. Pat. No. 6,565,840; alkyl ester basedcyanoacrylate adhesives including those disclosed in U.S. Pat. No.6,620,846; adhesives based on biocompatible cross-linked polymers formedfrom water soluble precursors having electrophilic and nucleophilicgroups capable of reacting and cross-linking in situ, including thosedisclosed in U.S. Pat. No. 6,566,406; two part adhesive systemsincluding those based upon polyalkylene oxide backbones substituted withone or more isocyanate groups in combination with bioabsorbable diaminecompounds, or polyalkylene oxide backbones substituted with one or moreamine groups in combination with bioabsorbable diisoycanate compounds asdisclosed in U.S. Published Patent Application No. 2003/0032734, thecontents of which are incorporated by reference herein; and isocyanateterminated hydrophilic urethane prepolymers derived from aromaticdiisocyanates and polyols as disclosed in U.S. Published PatentApplication No. 2004/0115229, the contents of which are incorporated byreference herein.

Examples of adhesives which can be employed include protein derived,aldehyde-based adhesive materials, for example, the commerciallyavailable albumin/glutaraldehyde materials sold under the tradedesignation BioGlue™ by Cryolife, Inc., and cyanoacrylate-basedmaterials sold under the trade designations Indermil™ and Derma Bond™ byTyco Healthcare Group, LP and Ethicon Endosurgery, Inc., respectively.Examples of sealants, which can be employed, include fibrin sealants andcollagen-based and synthetic polymer-based tissue sealants. Examples ofcommercially available sealants are synthetic polyethylene glycol-based,hydrogel materials sold under the trade designation CoSeal™ by CohesionTechnologies and Baxter International, Inc.

In certain preferred embodiments, the wound treatment material “W”includes a sealant which is desirably a PEG-based material. Examples ofclasses of materials useful as the sealant and/or adhesive includeacrylate or methacrylate functional hydrogels in the presence of abiocompatible photoinitiator, alkyl-cyanoacrylates, isocyanatefunctional macromers with or without amine functional macromers,succinimidyl ester functional macromers with amine or sulffiydrylfunctional macromers, epoxy functional macromers with amine functionalmacromers, mixtures of proteins or polypeptides in the presence ofaldehyde crosslinkers, Genipin, or water-soluble carbodiimides, anionicpolysaccharides in the presence of polyvalent cations, etc. Examples ofsealants, which can be employed, include fibrin sealants andcollagen-based and synthetic polymer-based tissue sealants. Examples ofcommercially available sealants are synthetic polyethylene glycol-based,hydrogel materials sold under the trade designation CoSeal™ by CohesionTechnologies and Baxter International, Inc.

Surgical biocompatible wound treatment materials “W” which may be usedin accordance with the present disclosure include adhesives whosefunction is to attach or hold organs, tissues or structures. Examples ofadhesives which can be employed include protein derived, aldehyde-basedadhesive materials, for example, the commercially availablealbumin/glutaraldehyde materials sold under the trade designationBioGlue™ by Cryolife, Inc., and cyanoacrylate-based materials sold underthe trade designations Indermil™ and Derma Bond™ by Tyco HealthcareGroup, LP and Ethicon Endosurgery, Inc., respectively.

Some specific materials which may be utilized as adhesives includeisocyanate terminated hydrophilic urethane prepolymers derived fromorganic polyisocyanates and oxyethylene-based diols or polyols,including those disclosed in U.S. Pat. Nos. 6,702,731 and 6,296,607 andU.S. Published Patent Application No. 2004/0068078; alpha-cyanoacrylatebased adhesives including those disclosed in U.S. Pat. No. 6,565,840;alkyl ester based cyanoacrylate adhesives including those disclosed inU.S. Pat. No. 6,620,846; adhesives based on biocompatible crosslinkedpolymers formed from water soluble precursors having electrophilic andnucleophilic groups capable of reacting and crosslinking in situ,including those disclosed in U.S. Pat. No. 6,566,406; two part adhesivesystems including those based upon polyalkylene oxide backbonessubstituted with one or more isocyanate groups in combination withbioabsorbable diamine compounds, or polyalkylene oxide backbonessubstituted with one or more amine groups in combination withbioabsorbable diisoycanate compounds as disclosed in U.S. PublishedPatent Application No. 2003/0032734, the contents of which areincorporated by reference herein; and isocyanate terminated hydrophilicurethane prepolymers derived from aromatic diisocyanates and polyols asdisclosed in U.S. Published Patent Application No. 2004/0115229, thecontents of which are incorporated by reference herein. It iscontemplated that any known suitable adhesive may be used.

The stent can be an absorbable or resorbable polymer, stainless steel,titanium, or other bio-compatible material.

It will be understood that various modifications may be made to theembodiments disclosed herein. For example, various other supportstructure may be provided on the pusher to engage, support, and advancethe adhesive coated stent out of the insertion instrument. Further, asnoted hereinabove, the disclosed deployment cartridge, including thepusher and adhesive coated stent, may be utilized in insertioninstruments other than stapling instruments. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of particular embodiments. Those skilled in the artwill envision other modifications within the scope and spirit of theclaims appended hereto.

1. An insertion instrument for positioning a stent at an anastomoticsite in the intestine of a patient, comprising: an annular surgicalstapling device, having an anvil member and a tubular member, the anvilmember having a cap and a shaft, the tubular member terminating in ahead portion carrying a plurality of surgical staples individuallydisposed in a plurality of staple pockets arranged in an annularconfiguration, the anvil member shaft being connectable to the tubularmember radially inwardly of the surgical staples, the head portionhaving a recess therein; an inner ring of staple pockets disposedradially inwardly of the recess; and a stent disposed in the recess ofthe head portion, radially inwardly of, and separate from, the surgicalstaples, wherein the stent includes an outer coating that is configuredfor non-mechanical fixation to the intestine of the patient.
 2. Theinstrument according to claim 1, comprising a deployment cartridgehaving a pusher for retaining the stent in the recess of the headportion.
 3. The instrument according to claim 2, wherein the deploymentcartridge includes at least one support member for supporting the stent.4. The instrument according to claim 2, wherein the deployment cartridgeincludes a sharp edge.
 5. The instrument according to claim 2, whereinthe deployment cartridge is a generally tubular cartridge.
 6. Theinstrument according to claim 1, wherein the stent comprises a meshhaving a generally tubular structure.
 7. The instrument according toclaim 6, wherein the stent has an adhesive material disposed as theouter coating on an outer surface thereof.
 8. The instrument accordingto claim 1, wherein the annular stapling device further includes anouter ring of anvil pockets and an inner ring of anvil pockets disposedradially outwardly and inwardly of an abutment surface.
 9. Theinstrument according to claim 1, wherein the stent includes a centrallyweakened area.
 10. The instrument according to claim 1, wherein thestent includes an inwardly directed circumferential recess.
 11. Theinstrument according to claim 1, wherein the stent is wholly disposedwithin the recess.
 12. The instrument according to claim 1, wherein thesurgical staples and the stent are separately driveable from the headportion of the tubular member.